Possibly dry air desiccating your sinuses? Our houses tend to dry out during winter because the heat is on, and dry sinus can cause headaches. Maybe get a humidifier and see if it helps?
I hate that, because the best cure for a headache is sleep, and you can't if you just woke up.
Water, excedrin, coffee, shower, sex and nap. I usually wake up without the headache.
are you drinking water? Maybe an aspirin before you drop off at night?
How, I have no idea what is causing it!
Listen to a rock band.
painkillers and water loads of it